I have a 86 760 Turbo which has been sitting under trees for a few years
The oil level was fine but after driving 50 miles it went down 2 litres!!
It isn't burning out the exhaust, It's leaking onto the exhaust pipe. Any ideas? I was told the rear main rarely goes on these things.
Hard to tell where exactly it's coming from.

Your distributor has two oil ring seals and they also go bad. This causes a huge oil leak down the back of the block

Thanks I will check this area. I do recall seeing a drip of oil under the distributor however I can never see it flowing out as it seems to do it more as speed rises. For example it goes through more quickly on the highway. More preassure created obviously

Check the turbo oil return seal at the block. Your rear main could indeed be going.

Thanks will check this out

If your model has the distributer up front, then check to see is the rear cam plus has blown out. (In later models, I believe the distributor was moved to the rear, and now occupies the port where the cam plug used to be)

Be sure yoou service the positive crankcase ventilation components ("Y" connector above the oil separator box and the box, itself) Clean out any plugged hoses, intake manifold nipples, etc.
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1989 740Ti 1986 240DL 1984 244GL

ok will check these areas out, thanks

valve cover gasket?
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Kenric Tam
1990 Volvo 740 base sedan (B230F)
My Volvo 'Project'

The valve cover gasket shows some signs of leaking. I had tightened the bolts however there is not enough evidence in this area to support the amount of oil leaking out.